Stress and depression are among the most prevalent neuropsychological conditions affecting modern society. While acute stress may serve adaptive functions, chronic stress and depressive disorders exert profound negative effects on the central nervous system. These conditions are associated with structural, functional, and biochemical alterations in the brain, leading to impaired cognition, emotional dysregulation, and increased vulnerability to neurological and psychiatric disorders. This article provides a comprehensive clinical and neurobiological review of the effects of stress and depression on the central nervous system. Particular attention is given to hypothalamic–pituitary–adrenal HPA axis dysregulation, neurotransmitter imbalance, neuroplasticity impairment, and neuroinflammatory processes. Understanding these mechanisms is essential for improving diagnostic accuracy, therapeutic strategies, and preventive interventions.

Stress, depression, central nervous system, HPA axis, neuroplasticity, neurotransmitters, neuroinflammation.

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